You can export a notebook as a web page in the Wolfram Cloud using CloudExport. You can also programmatically deploy content to web pages using CloudDeploy. Note: make sure that your Wolfram Cloud Account is set up to allow you to deploy web pages in the Wolfram Cloud.

This deploys a simple HTML document to the cloud:

The deployed page is viewable by clicking the link:

CloudDeploy can also be used with ExportForm to set up web pages on the cloud:

If the HTML you are deploying is not a complete document, the "HTMLFragment" format should be used.

This deploys an HTML fragment as a web page:

Clicking the link shows that the fragment has been made into a full HTML document: